I. Field of the Invention
This invention relates to a device and a method for accurately positioning a probe in a bodily protuberance relative to a target located in the protuberance. In particular, the invention relates to securing the protuberance and positioning a probe tip proximate the target within the protuberance through the use of radiographs and certain radiopaque markers where the markers are, in part, positioned coplanar to the target and appear in the radiographs.
II. Description of Related Art
The detection of lesions in bodily protuberances, such as the breasts, has been aided in recent years through the use of mammography. One commonly used method of confirming breast cancers related to lesions targeted from a mammogram involves sampling suspect tissue from the target lesion through a biopsy procedure.
The biopsy procedure typically involves positioning a barbed guide wire in the vicinity of or directly in the targeted lesion. A surgeon then follows the wire through the breast tissue to the suspect lesion. The surgeon removes the suspect tissue and the removed tissue is examined for abnormalities such as cancerous cells.
Approximately only one in five such lesions are cancerous. Thus, significant surgical expertise, time, expense and patient suffering result from the approximate four out of five biopsies that show no cancerous cells.
Recently, a less invasive procedure has been developed using mammography and a needle to aspirate cells of the lesion from the body. The aspirated cells may then be examined using known cytopathologic techniques to determine the presence or non-presence of cancerous cells.
In utilizing the needle aspiration procedure, it is imperative that the needle tip be placed with precision at the targeted lesion to insure that the cells aspirated are the cells of the targeted lesion and not merely cells near the lesion.
Precise location of the needle tip for needle aspiration may be accomplished utilizing a stereotactic instrument having an x-ray tube mounted on a hinged arm positionable at precise angles relative to known coordinates. Such devices while enabling accurate needle tip location, are typically costly and often not readily available.
The device and method of the present invention provide a relatively low cost approach to precision location of a needle tip in a breast or other protuberance relative to a targeted lesion.